A conventional seat type of flush toilet as shown in: FIG. 1 comprises a water tank "A", a hopper lid "B", a toilet seat "C" and a hopper "D"; the water tank "A" has a flush handle "E" for controlling the water in the tank to flush into the hopper "D" so s to flush away the waste in the hopper; however, the toilet seat "C" of such conventional flush toilet has to be lifted up and laid down manually and repeatedly during use. The user of such flush toilet would: feel inconvenient to use the same, and further, since a user's hand has to touch such toilet seat upon using, a sanitary consideration will be involved; moreover, when a user's hand presses the flush handle "E", a sanitary consideration can also be involved; in other words, such conventional flush toilet has the drawbacks of sanitation and operation.